Conan’s debut lures the 18-to-49 crowd

Conan O’Brien finished his first week on TBS with a hefty and remarkably younger-skewing audience.

Thursday’s show drew 2 million viewers, less than half the number who gathered for his much-awaited debut on Monday, according to the Nielsen Co.

But nearly 1.4 million were in the 18-to-49 age group that many advertisers want to reach.

All week, the cable network crowed about the median age for “Conan” viewers: about 30, while the late-night talk shows on the broadcast networks typically crack the 50-year-old mark, or push past it.

For “Conan” – which airs Mondays through Thursdays at 11 p.m. – the big question becomes: How many more viewers will fall away as his new show’s core audience reveals itself?

The answer could be coming as soon as this week.

“I think by then, Conan will be close to where he’s going to end up,” media analyst Steve Sternberg says. “And if he maintains an audience of 1 million 18- to 49-year-olds, I think TBS will be happy with him.”

After eight months on the sidelines after his brief stint hosting “The Tonight Show,” and his bitter exit from NBC last January, O’Brien returned to late night amid much media attention as viewers flocked to welcome him back.

“He was almost like a folk hero,” said analyst Shari Anne Brill. “A lot of people were tuning in for curiosity’s sake.”

Looking rested, ready and typically self-skewering, O’Brien greeted guests including “Mad Men” star Jon Hamm; Julie Bowen of “Modern Family”; and the clearly-game-for-anything Tom Hanks, who, while chatting with O’Brien on Tuesday’s show, was drenched by a diving whale (you had to be there).

On Wednesday, he shared a list of rejected titles for his new show. Among them were “Plan B With Conan O’Brien,” “One Hour to Lopez” and “One Night Closer to Death.”

“We’ve been having a great first week here at TBS,” he said during Thursday’s monologue. “But if this doesn’t work out, you can catch me next fall on my new VH1 show, ‘Coning for Love.’ ”